Wireless networks bring voice and data communications to both mobile and stationary users. The present invention is particularly suited to two types of wireless networks. The first type of wireless network is called a wireless local area network (WLAN or Hotspot) where data and voice communications are provided within a building or within close proximity of a building. In a WLAN, users typically employ laptop computers with antennas that communicate with wall-mounted antennas connected to a wired network. The second type of wireless network is called a wireless metropolitan area network (WMAN) where data and voice communications are provided to residential and business premises via radio links that connect to the Internet backbone. The radio links are typically obtained by mounting antennas on houses and lampposts. Additionally, the present invention may be well suited for other types of wireless networks.
In wireless networks, the data signals are transmitted through air, so there is no shield protecting transmitted signals from eavesdroppers. For this reason, it is more difficult to create a secure wireless network than a secure wired network. Unauthorized users of a wireless network may potentially gain access to the network to actively steal information and change network parameters.